My Grandmother died in Dallas, Tx, 12/01/1979. There was not a court administration on either the estate of Washington Phillips (my grandfather) or Elector Steen Phillips. There was an 80 acre estate left open. Each sibling was to receive 1/5 portion of the land. A land developer claims to have acquired 4/5 of the land from four siblings, one being my father, in 1996. My father was declared incompetent by the State of Florida in 1959. I had proof that i sent to the developer. There has been no attempt to return the land to my father. Since my father's death in 2007 I feel I have the rights to the land. Do I have the right to claim the land, and what steps can I take?